Electric iron



F. KUHN ET AL Oct. 11, 1932.

ELECTRIC IRON Filed April 28. 1930 wm /m'mm Patented oa. 11, 1932 UNITED STATES PATENT OFI-Ice FRANK KUHN, F DETROIT,AND LAURENCE H. THOMAS,- OF BIRMINGHAM, :MIICIEICtAl-"9 ASSIGNORS TO AMERICAN ELECTRICAL HEATER COMPANY; 0F DETROIT, MIIEIGAXs A CORPORATION OF MICHIGAN ELECTRIC IRON Application lec'i April 28,

This invention relates generally to electric heaters and more particularly to thermostatically controlled electric irons and has as one of its objects to cheapen the cost of manufacture and facilitate assembly by simplifying the construction ofthe several parts involved and by reducing the number of such parts to a minimum. y

The invention provides for simplifying the construction and facilitating assembly by 'introducing improved means for supporting a thermostatic j switch assembly within the heater permitting the switch assembly to be readily removed from and assembled with the heater as a unit. v

With the above as well as other objects in view, the invention resides in the novel details of construction which will be made more apparent as this -description proceeds, especially when considered in connection with the accompanying drawing, wherein:

Figure 1 is a fragmentary sectional view through an electric iron constructed in accordance with this invention. Y

Figure 2 is a fragmentary top plan view of the construction shown in Figure 1 with certain parts broken away for the sake of clearness.

Figure 3 is an end elevational view of the construction shown in Figure 2.

f Figure 4 is a sectional view taken on the line 4-4 of Figure 2. i

v:Referring now to the drawing, it will be noted that there is illustrated in Figure 1 an electric iron comprising a heating element 11 clamped between the pressure plate 13 and A theheat'distributing base plate 14 by means of the fastener elements 15 having the head portions v thereof Aengagingthe top surface 16 of the pressure plate and having the shank portions extending through suitable aligned openings in-.the lattery plate and heating element andthreadedly engaging the base plate 14. The above parts of the iron; are preferably inclosedby a suitable cover or hood 17 seated upon the'base plate 14 and'having the conventional handle secured thereto in any suitable manner.

For controlling the operation of the heat.- ing element, we provide a switch unit desigv strip 24 is prevents raso. serial no. 443,099.

nated generally by the reference character 13 and comprising a bracket 20 arranged within an elongated opening 21 formed in the pressure plate 13 and having a portion 22 for supporting a pair of cooperating thermostatic strips 23 and. 24 in close proximity to the heat distributing plate 14 of the iron so as to receive heat mainly therefrom. is shown in Figure 1, the strips- 23 and 24 are disposed within a recess 25 formed in the base plate and are arranged in s'uperposed relation. The fixed ends of the strips 23 and 24 are secured to the portion 22 of the bracket 20 by means of a fastener element 26 which also serves to secure the terminal members j 2'? and 28 to 'the strips 23 and 24, respectivel7 As shown in Figure 3, the terminal 28 is elecm trically connected 'to one end of the heating coil formingthe heating element, while the terminal 27 is electrically connected to a source of electric energy in a manner tobe presently described. rllhe construction is such that the thermostatic stri s 23 and 24 are connected in series with t e circuit to the heating element for controlling the operation thereof.

The bracket 2O is provided with another portion 29 spaced above the portion 22 and adapted to project beyond the same as clearly illustrated in Figure 1. The portion 29 of the bracket is provided with a threaded open ing 30--therein adjacent the free end thereof for adjustably receiving a sleeve 31. The sleeve 31 is provided with an internally threaded bore for adjustably receivingl a,

,regulating element 32. The lower portion of the regulating element 32 is provided with anenlarged head 33 arranged in the path or" travel of a projection 34 extending upwardly from the lowermost thermostatic strip 24 adjacentthe free end thereof. 4The arrangement is such that when the iron reaches al certain predetermined temperature, the free ends of the stri s 23 and 24 are-moved upwardly under the mfluence of the heat unj til the projection 34 engages the/head .33 at which time further upward movement of the As the temperature continues to rise the upper stri v23 moves A away from the strip 24 breaking t e electrical '10 n connection therebetween and silice the therthe sleeve 31.

-mostatic strips are connected in the circuit to the heating element, the flow of current to the latter is discontinued. The temperal jectsthrough the hood 17 and detachably engages a suitable operating member 35. The extent of adjustment of the regulating member 32 is limited by a stop 36 projecting laterally from the head portion 33 in the path of travel of a fixed stop 37 depending fromv a flexible strip 38 yintermedlate the ends of the latter.v One end of the strip 38 is secured to the under surface lof the portion. 29 of the bracket by means of a fastener element 40 while the opposite end of the -lexible member is adapted to engage the head portion 33 to compensate for any back lash between the threads of the regulating member 32Vand the sleeve 31. As set forth above, the sleeve 31 is threadedly mounted upon the portion 29 of the bracket so as to be capable of axial adjustment. By

virtue of this latter arrangement, the initial position of the regulating member may be accurately determined so as -to give the desired range of adjustment. This adjustment may be accomplished from' without the iron by merely detaching the'control lever 35 and inserting a suitable tool through the opening 35T to engage the tool engaging portions 36 of the sleeve 31.

In order to rigidly support the bracketl20 within the recess `21 in the pressure plate, we provide a plate 41 seated upon the top sur- ',face 16 ofthe pressure plate and detachably .seured thereto by means of the fastener elements 15, hereinbefore discussed. The plate 41 is rigidly secured to the portion 29 of the bracket by means of the fastenerelement 40, -above referred to, which, as shown in Figure 1, extends through a suitable aperture in thev 'hood 17 for engagement by the nut 42. The

lconstruction vis suchj that the fastener element 40, in addition to securing the plate and exible member to the bracket to form a unitary construction therewith, also functions tofdetachably securethecover in assembled relatipn upon the'heat distributing 'base plate 14 of the iron.

For connecting the heating element, and

switch to asource of electrical energy, we

' provide a pair of'terminal members 43 and 44 having portions secured-to the plate 41 by means of the fastener elements 45 and46 and having other portions, extending upwardly from the plate through the hood portion of the iron for engagement with the conventional electric plug or the like. The terminal'43 is electrically connected by means of the conductor 47 to the terminal 27 for the thermostatic strip 23, while the terminal 44 is electrically connected to the free end of the heating coil, the opposite end of which bein connected to the terminal 28 as pointed out a ove. rlhe arrangement is such as to establish a circuit from the' supply of electrical energy through the heating element and thermostatic strips 23 and 24.

Thus, from the foregoing it will be observed that we have provided a mounting for a switchunit upon an electric iron in the form of the plate 41 Vwhich serves to secure the thermostatic strips, terminals for the strips, means for regulating the Aoperation of the thermostatic strips, means for holding the a heating element, saidl assembly Jcomprising thermostatic `members for controlling the operation of the heating element, a bracket having a portion supporting the members aforesaid in close proximity tothe base late of the iron so as to receive heat mainly t erefrom `and having another portion extending. upwardly through an opening in the pressure plate of the iron, a member supported on the pressure plate and secured to said bracket for supporting the latter in'position within the iron andterminal members carried by said latter member and extending upwardly therefrom for electrically' connecting said heating element and switch to a source of electric nergy. v i

2. A switch assembly for an electric, iron having a base plate, a pressure plate and a heating element, said assembly comprising l /thermostatic members for controllin the opera-tion of the heating element, a brac etl having Ya portion suppprting the members in close proximity to t c `so as to` receive heat mainly' therefrom and .having anothevr portion projecting upwardly,` through an opening in the pressure, plate ofthe iron, a member seated u on the top e base. plate' of the iron yme surface of the pressure plate an secured to said bracket for supporting the latter 'in posi;l tionl within the' iron, regulating means carried by said bracket and operable to control'r the temperature atfwhich said thermostatic members are-adapted to operate, means for electricall connecting the heating element and swit'c to a source of electric energy in- 180 cluding terminal members secured to said last-.mentioned member.

3. A switch 'assembly for an electric iron having a base plate, a pressure plate and a heating element, said assembly comprising thermostatic members for controlling the operation of the heating element, a bracket having a portion supporting the thermostatic members in close proximity to the base plate of the iron so as to receive heat mainly therefrom and having another portion projecting upwardly through an opening in the pressure plate of the iron, a plate seated upon the top surface of the pressure plate and detachably secured thereto, means for securing the plate to the bracket forming a unitary construction therewith and terminal members secured to said plate and electrically connected to the heating element and switch.

4. A switch assembly for an electric iron having a cover, a base plate, a pressure plate and aheating element, said assembly coinrising thermostatic members for controllinfr b D the operation of the heating element., a bracket arranged within a recess in the pressure plate of the iron and having' a portion for supporting the thermostatic members in close proximity to the base plate of the iron so as to receive heat mainly therefrom, a plate seated upon the top surface of the pressure plate and detachably secured thereto, means for securing both the plate to the bracket and the cover for the iron in assembled relation with the latter Vand terminal members carried by the plate and extending upwardly therefrom through the co`ver for the iron.

In testimony whereof we affix our signatures.

lFRANK KUHN. LAURENCE H. THOMAS.

^ 5. A switch assembly for an electric iron having a. cover, a base plate, a pressure plate and a heating element, said assembly comprlsing thermostatic members for controlling the operation of the heating element, a brackl et for supporting the member in. close proximity to the base plate of the iron so as to receive heat mainly therefrom7 a plate seated upon the top surface of the pressure plate and detachably secured thereto, means carried by said plate for securing the latter to the bracket to form a nnitary'construetion therewith and` for detachably securing the cover for the iron in assembled relation with the latter, and terminal members securedto v said plate and electrically connected tothe lheating element and thermostatie switch.

6. A-switch assembly for an electric iron havinga base plate, a pressure plate and a heating element," said assembly comprising 

